Doubt regarding session_destroy() in PHP 5

Hi all, I have a doubt with creating and destroying sessions in PHP using session_destroy(). Supposing there is a PHP-based website hosted on a web server. Now I add another site that I developed using PHP on that web server using virtualhost. I destroy a session in my website using session_destroy() which will destroy all the session variables associated with my website. What will happen if I have the other website in another tab with similar session variable names? Will the session variables of that website be destroyed too? Or will the session variables be associated with the session id so that only the appropriate website's session variables will get destroyed? Thanks in advance. Regards, Guruprasad